docs: def timezone(self):
          """The name of the time zone for the location.
  
          A list of time zone names can be obtained from pytz. For example.
  
          >>> from pytz import all_timezones
          >>> for timezone in all_timezones:
          ...     print(timezone)
          """
  
          if not self._timezone_group and not self._timezone_location:
              return None
  
          if self._timezone_location != "":
              return "%s/%s" % (self._timezone_group, self._timezone_location)
          else:
              return self._timezone_group